Influence of dopants Cu, Ga, In, Hg on the electronic structure of CdnSn (n = 6, 15) clusters – a DFT study. Issue 95 (28th September 2016)

• Record Type: Journal Article
• Authors: Ganesan, Paramasivam; Lakshmipathi, Senthilkumar
• Is Part Of: RSC advances. Volume 6:Issue 95(2016)
• Page Start: 93056
• Page End: 93067
• Publication Date: 2016-09-28
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c6ra15049g
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : The influence of dopants on the electronic structure and the optical properties of doped Cd n − y X y S n ( n = 6, 15; y = 1, 2, 4) clusters, studied using DFT and TDDFT methods. Abstract : The influence of doping metal ions on the structural, electronic and optical properties of Cd n − y X y S n ( n = 6, 15; y = 1, 2, 4) clusters is systematically studied using DFT and TD-DFT studies. Among the dopants, Cu 2+ and In 2+ slightly distort the structure of Cd n S n clusters, though they have a strong bonding interaction with S 2− however; another two dopants Ga 2+ and Hg 2+ significantly distort the cluster's structure. Molecular composition analysis reveals the dopants not only contribute to the optically active states, but also to the surface or trap states. The HOMO–LUMO gap is significantly reduced for Cu 2+, Ga 2+, and In 2+ dopants. However, for Hg 2+ the gap is meagerly affected. In large clusters, Cd15 S15, the polarizability values decrease on doping, though individual dopants show a nonlinear pattern. The absorption spectra of doped CdS clusters are generally red shifted though a few Ga and In clusters exhibit a blue shift due to the Burstein–Moss effect.